Since the specific objectives of replacing the Halon fire extinguishing agent were proposed to each country by The Canada Montreal Convention in 1987, all the countries of the world were dedicated to the research of new fire extinguishing technologies; people have made great efforts in order to find a fire extinguishing technology which has high fire extinguishing efficiency and no environment pollution.
The gas fire extinguishing systems, the powder fire extinguishing systems, the water type fire extinguishing systems and the like, which are environmentally friendly, are widely used as the substitutes of the Halon fire extinguishing agent. The fire extinguishing mechanism of an inert gas fire extinguishing system, such as carbon dioxide, IG541 and the like, is mainly based on physical extinguishing, namely, smothering extinguishing by reducing the oxygen concentration in a fire area, such fire extinguishing method will easily threaten the safety of the individuals. The powder fire extinguishing system implements fire extinguishing via the process in which the sprayed powder contacts with the flame under the force of pressurized gas to generate the physical and chemical inhibition effect; the water spraying fire extinguishing system achieves the purpose of controlling the fire, inhibiting the fire and extinguishing the fire under triple roles of cooling, smothering and isolating thermal radiation of the water mist.
However, these fire extinguishing systems need to be stored under high pressure, not only causes larger volume, but also have the risks of physical explosion during storage process; the document “The Security Analysis of Gas Fire extinguishing System” (Fire Science and Technology 2002 21(5)) analyzes the risks of the gas fire extinguishing system, and enumerates the safety accidents caused by the storage pressure gas fire extinguishing system when in use.
In recent years, people have been researching the fire extinguishing substances which can replace Halon, wherein the Next Generation Fire Extinguishing Technology Project Group (NGP) of the Building and Fire Research Centre of the U.S. National Institute of Standards and Technology (NIST) did a large number of experimental researches in the aspect of finding new fire extinguishing substances, the process includes: heating nitrogen, carbon dioxide and CF3H gas, and then using the heated high-temperature gas to heat the test substances; the test substances are then decomposed under high temperature, which acts on the flame together with the gas; Through the experiments, people find that the products generated by heating and decomposing some test substances can obviously improve the fire-extinguishing effect of the nitrogen, carbon dioxide and CF3H gas (Halon Options Technical Working Conference, April 2001, Albuquerque, N. Mex., Suppression of cup-burner diffusion flames by super-effective chemical inhibitors and inert compounds; Combustion and Flame 129:221-238(2002) Inhibition of Premixed Methane Flame by Manganese and Tin Compounds, Halon Options Technical Working Conference May 2000, flame inhibition by ferrocene, alone and with CO2 and CF3H).
However, the researches of the project group stopped after the laboratory theoretical research, without practically applying the research findings in fire extinguishers.
The existing aerosol fire extinguishing agent mainly includes the S type and K type fire extinguishing agents, by comprehensively analyzing the performance characteristics, the disadvantages are mainly as follows: all the aerosol fire extinguishing agents use the fire extinguishing agents to generate an oxidation-reduction reaction, which releases a large number of gas and active particles, finally to achieve the chemical and physical combination fire-extinguishing purpose via the chain scission reaction of the active particles and the coverage smothering of the large number of gas. The aerosol fire extinguishing agent can release a large amount of heat while releasing the aerosol during the combustion reaction; in order to effectively lower the temperature of the device and the aerosol, and to avoid a secondary fire, a cooling system needs to be added, which causes complicated and heavy device structure, complicated technical process and high cost; because of the existence of the cooling system, a large number of active particles are inactivated, and the fire extinguishing performance is greatly reduced.